Accessory Device for an Orthopedic Fixator

ABSTRACT

An accessory device for an external orthopedic fixator where the fixator has an external frame made up of frame components which surround the lower leg and ankle of a patient with one or more transfixation wires fixed thereto. The accessory device includes a foot plate which connects to one of the fixator frame components for supporting the sole of a patient&#39;s foot. The accessory device also includes a companion shroud which is wrapped about the fixator with the fixator being received within the interior of the shroud. The shroud has a width and height which are sufficient to conceal the fixator within the shroud interior. The shroud has fabric hook and loop fastener regions which allow it to be easily installed and removed from about the fixator.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to therapeutic devices used for fixating and immobilizing limbs, particularly a patient's foot and ankle and, more specifically, to an Ilizarov-type external fixator and to an accessory cover or shroud for a fixator of this general type.

2. Description of the Prior Art

There are many types and classes of braces and other orthopedic devices for fixating and immobilizing a patient's limbs due to various medical conditions. For example, when a bone is fractured, it is often necessary to hold the fragments of the bone together to allow for correct healing. If this is not done, problems such as misalignment or poor healing can occur.

In the field of foot and ankle surgery and recovery, multiple options exist for stabilizing a patient's foot after surgery. One option, referred to in the field as a “fixator,” has transfixation wires, pins or screws that extend into and through bone segments in order to stabilize the bones. The external fixator typically takes the form of a steel rod, collar, or other external frame element spanning across the fracture which is fixed to the bone fragments using the wires, pins or screws. The frame elements are located outside the body, while the pins or similar elements penetrate the skin and are fixed in the bone. Other external braces including a wide range of removable casts and ankle braces are also known.

One preferred class of external fixators is referred to in the field of orthopedics as the “Ilizarov” device, named for the inventor of the device. This device uses thin wires and external fixator frame components to properly place segments of bone for purposes of reconstruction of fractured or deformed extremities following orthopedic surgery. Frames used in these types of procedures are arranged crosswise in pairs or individually in each ring or ring-section level, whereby the various rings are connected to each other by means of rods and bolts. The intervals of the ring levels can be adjusted by rods whose lengths can be varied telescopically, or by bolts that can be adjusted. Frames of this type are now commonly in use for a variety of orthopedic applications including limb lengthening, stabilization and positioning of open fractures, and in the structural correction of a multitude of lower extremity deformities such as the correction of angulation, rotation and translation.

Another general type of orthopedic device that may be used as a therapeutic or surgical recovery brace is sometimes referred to informally as the “cam boot” and may resemble a ski boot in outward appearance. However, the cam boot functions as a type of functional splint or cast which holds the foot in a neutral position while healing takes place after a surgery. A cam boot is noninvasive and can, in some instances, successfully immobilize the extremity during the healing process. Also, cam boots are removable. While appropriate in many situations and for multiple types of surgeries, a cam boot is not an option when performing surgeries to correct many foot injuries or deformities.

While the Ilizarov-type device provides a much more stable platform for recovery in many surgical situations than the cam boot, the appearance of the external fixator with its cross wires, pins and ring elements can be embarrassing or unsightly to some wearers or observers. Additionally, the exposed nature of the embedded pins and the rings and other external fixator elements presents the added danger of accidentally bumping these components, causing pain and discomfort, or even additional injury to the patient.

What is needed is an effective cover or shroud for the Ilizarov fixator which would essentially conceal the fixator while the fixator is in place on a patient, especially in public situations.

The cover or shroud should be easily removable, as at night, and should be made of materials which provide adequate concealment, while also being durable and long lasting and which also add an element of additional protection to the wearer from accidental bumps or jolts.

The cover should also include a foot plate component which attaches to an element of the Ilizarov fixator frame to provide added stability for the entire assembly.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a cover or shroud and companion foot plate for an Ilizarov type fixator which meets the aforementioned needs. More specifically, the accessory device of the invention is designed for use with an external orthopedic fixator used to stabilize a patient's foot and ankle, where the fixator has an external frame made up of a plurality of frame components which surround the lower leg and ankle of a patient with one or more transfixation wires fixed thereto.

The foot plate, which forms one element of the combination accessory device of the invention has an upper surface used for supporting the sole of a patient's foot and has an oppositely arranged lower surface and an intermediate thickness. The foot plate has a plurality of connector elements mounted thereon. The connector elements have exposed upper extents extending upwardly from the upper surface of the foot plate, the upper extents being matingly engageable with at least one of the frame components of the fixator for securing the foot plate to the fixator and for supporting the patient's foot. The foot plate also has a peripheral outer edge which includes a connector region.

The other component of the accessory device of the invention comprises a flexible shroud having an overall width and height, an exterior and an interior. A longitudinal seam, running vertically from the top to the bottom of the shroud, allows the shroud to be wrapped about the fixator with the fixator being received within the interior of the shroud and then secured in place. The shroud width and height are sufficient to conceal the fixator when the fixator is so received. In one preferred form, the shroud has a lower peripheral edge which is provided with a connector region for matingly engaging the connector region of the foot plate. The longitudinal seam of the shroud also includes a connector region for securing the shroud about the fixator. The footplate connector region and the shroud connector region can conveniently comprise hook and loop type fabric connector regions.

The shroud body can be formed of a number of commercially available materials, but is preferably formed of a synthetic fabric material, the interior of the shroud being provided with a layer of protective plastic which reinforces and protects at least a portion of the interior surface thereof from the components of the fixator.

In one form of the invention, the connector elements which are provided on the footplate are threaded bolts which have exposed threaded extents which protrude upwardly from the upper surface of the foot plate. The frame component of the fixator, which is used for securing the foot plate to the fixator and for supporting the patient's foot, comprises at least one support collar having a plurality of openings therein, the openings being spaced in alignment with the exposed extents of the threaded bolts for receiving the bolts to thereby attach the foot plate to the fixator collar.

The assembled foot plate and shroud completely enclose the fixator from beneath and on all sides.

Additional objects, features and advantages will be apparent in the written description which follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a portion of a human leg showing an Ilizarov-type orthopedic fixator in place on the ankle and lower leg of the patient.

FIG. 2 is another view of an Ilizarov-type fixator showing the cross pins which penetrate the bone of the patient, with the bone being exposed for ease of illustration.

FIG. 3 is a perspective view of the accessory device of the invention with the shroud portion thereof shown exploded from the base portion thereof.

FIG. 4 is another perspective view of the accessory device of the invention in place on the lower leg of a patient, a portion of the shroud thereof being shown broken away for ease of illustration.

FIG. 5 is view of a prior art cam boot of the type used to stabilize the lower leg of a patient.

FIG. 6 is a view of another prior art device used to stabilize the lower leg of a patient.

DETAILED DESCRIPTION OF THE INVENTION

The preferred version of the invention presented in the following written description and the various features and advantageous details thereof are explained more fully with reference to the non-limiting examples included in the accompanying drawings and as detailed in the description which follows. Descriptions of well-known components and processes and manufacturing techniques are omitted so as to not unnecessarily obscure the principle features of the invention as described herein. The examples used in the description which follows are intended merely to facilitate an understanding of ways in which the invention may be practiced and to further enable those skilled in the art to practice the invention. Accordingly, the examples should not be construed as limiting the scope of the claimed invention.

Turning to FIG. 1, there is shown one form of an external fixator of the type under consideration, designated generally as 11, the fixator being received about the lower leg 13 of a patient. As will be evident from FIG. 1, the fixator 11 includes a plurality of frame components which take the form of stacked rings or collar elements 15, 17, 19, which, in this case, are held together by means of a series of threaded bolts 21. The collar elements 15, 17, 19, span across a fracture of the lower leg and are fixed to the bone fragments using wires, pins or screws, in this case wires 23. While different fixators may use, for example, various wires, pins, screws or like transfixation or cross-elements, in this discussion the term “wires” will be understood to mean any of these commonly used transfixation cross-elements. As shown in FIG. 1, the frame elements are located outside the body, while the wires or similar elements penetrate the skin and are fixed in the bone.

FIG. 2 is a simplified view of another Ilizarov-type fixator 25 which has upper and lower collar elements 27, 29, the collars being connected and supported by means of connecting bolt assemblies (e.g., assembly 31). The bone is shown exposed to illustrate the fact that the cross pins 33 actually penetrate the bone itself. It will be appreciated that there are a variety of Ilizarov-type devices that are arranged somewhat differently from those illustrated in FIGS. 2 and 3, but which all operate in a generally similar fashion.

Thus, with reference to FIG. 2, the intervals or spacing of the collar elements 27, 29 can be adjusted by movement of the adjusting bolt assemblies 31. As mentioned in the Background Discussion, frames of this type are now commonly in use for a variety of orthopedic applications including limb lengthening, stabilization and positioning of open fractures, and in the structural correction of a multitude of lower extremity deformities such as the correction of angulation, rotation and translation, and these general types of devices will be well known to those involved in the field of orthopedic surgery, as well as being described in a number of different medical texts and journal articles.

Turning now to FIG. 3, there is shown an orthopedic fixator accessory device of the invention, designated generally as 35. The accessory device 35 is intended to be used with an external orthopedic fixator of the type previously described which is used to stabilize a patient's foot and ankle, the fixator having an external frame made up of a plurality of frame components which surround the lower leg and ankle of a patient with one or more transfixation wires fixed thereto.

As shown in FIG. 3, the accessory device 35 of the invention is comprised of two cooperating components, a foot plate 37 and a shroud 39. Turning first to the foot plate 37, it will be seen to be a generally planar member having an upper surface 41 used for supporting the sole of a patient's foot and having an oppositely arranged lower surface 43 and an intermediate thickness (shown as “t” in FIG. 3). In one preferred form, the foot plate 37 is constructed with a 4-ply configuration with ⅛ inch high grade rubber with grooves for the lower surface 43, then a ¼ inch layer of semi-rigid polypropylene, then a ⅛ inch flat layer of rubber, and finally a ⅛ inch layer of Plastozote™ as the top layer 41. Plastozote™ is a high quality, lightweight closed-cell cross-linked polyethylene “memory foam”, manufactured by Zotefoams, PLC and is available commercially from a number of sources.

As can be seen in FIG. 3, the foot plate 37 has a plurality of connector elements, e.g., elements 45, 47, mounted thereon. The connector elements 45, 47 have exposed upper extents 49 extending upwardly from the upper surface 41 of the foot plate. The upper extents 49 are matingly engageable with at least one of the frame components of the fixator for securing the foot plate 37 to the fixator and for supporting the patient's foot. This is best illustrated in FIG. 4 of the drawings which shows a connector element upper extent 49 which is received within an opening in the frame collar element 51 and retained in position by the nut 53.

Returning briefly to FIG. 3, the foot plate 37 also has a peripheral outer edge which includes a connector region, illustrated in exaggerated fashion as the region 55 in FIG. 3. As will be explained in greater detail below, the connector region is used to temporarily afix the companion shroud 35 to the foot plate 37. The connector region can be, for example, covered with a hook and loop “Velcro™” type connector material which connects to a mating lower peripheral region (57 in FIG. 3) on the shroud.

With reference to FIGS. 3 and 4, it can be seen that the flexible shroud 35 has an overall width 14 (“w” in FIG. 4) and height (“h” in FIG. 4). The shroud also has an exterior 59, an interior 61, and a longitudinal seam 63 which allow the shroud to be wrapped about the fixator with the fixator being received within the interior 61 of the shroud. The shroud width and height are sufficient to conceal the fixator when the fixator is so received with the fixator being completely enclosed on all sides and from the bottom, by virtue of the foot plate 37. As has been mentioned, the shroud has a lower peripheral edge 57 which is provided with a connector region for matingly engaging the connector region of the foot plate 37. The longitudinal seam 63 of the shroud also includes a Velcro™ connector region for securing the shroud about the fixator. If desired, the longitudinal seam 63 and the peripheral edge 57 can be provided with additional connector elements, such as snap fastener type connector elements to further reinforce the positioning of the shroud about the fixator.

The shroud body can itself be formed of a variety of convenient materials. In one preformed form, the shroud body is formed of a synthetic fabric material, the interior of the shroud being provided with a layer of protective plastic (65 in FIG. 3) which reinforces and protects at least a portion of the interior surface thereof. Most preferably, the exterior of the shroud is a light weight, but tear resistant synthetic fabric with a thin sheet of flexible polypropylene on the interior side facing the fixator.

In use, the combination foot plate and shroud of the invention are used to temporarily conceal an external fixator of the type previously described. The foot plate is attached to at least a selected one of the fixator frame components so that the foot plate supports the patient's foot, as by passing the threaded bolts 45, 47 through the mating openings in the lower collar of the fixator and securing the bolts with nuts. The shroud 35 is then wrapped about the fixator and the patient's lower leg, whereby the fixator is concealed within the interior of the shroud. The shroud 35 is afixed to the foot plate by matingly engaging the connector region 57 on the lower peripheral edge of the shroud with the connector region 55 of the footplate 37. The shroud 35 is then further secured about the fixator by matingly engaging the connector regions 63 running along the longitudinal edges of the shroud seam.

The advantages of the combination accessory device of the invention can perhaps best be understood with reference to the prior art devices shown as FIGS. 5 and 6 of the drawings. FIG. 5 is intended to represent one form of the “cam boot” style of protective boot, designated as 65 in FIG. 5, which is sometimes used as a therapeutic or surgical recovery brace. The cam boot can be seen to resemble a ski boot in outward appearance. In the case of the cam boot shown in FIG. 5, however, the boot functions as a functional splint or cast with a protective sheath and straps 67 which hold the foot in a neutral position while healing takes place. While this type of appliance has the advantages of successfully immobilizing the extremity in certain types of medical situations, and also being removable, the cam boot is not an option when performing surgeries to correct many foot injuries or deformities. Among other differences, the cam boot is completely external and does not feature the internal, transfixation elements that the Ilazarov-type device utilizes.

FIG. 6 illustrates another type of prior art device, generally described in issued U.S. Pat. No. 6,964,663, issued Nov. 15, 2005, to Grant et al., and designated as 69 in FIG. 6. The Grant device has a lower collar element 71 for connection to elements of an Ilizarov-type device. A substantially rigid leg support assembly 73 is adapted to receive a patient's leg, the leg support comprising a cuff and a strap adapted to secure the cuff around the patient's leg, The leg support is rigidly attached to the foot plate 75. The function of the rigid leg support in the device shown in FIG. 6 is obviously to allow the patient's foot to be fixed, with transfixation wires, or pins or screws and simultaneously immobilized with respect to the ankle and lower leg. The rigid leg support is an “internal” feature of the design and does not function to conceal or completely enclose the Ilizarov frame components. In fact, the lower collar component with its associated hardware remains exposed in use. The device would thus fail to provide the esthetic improvement that Applicant's device offers, and fail to provide the type of protection from bumps or other possible injury related occurrences that Applicant's device is intended to provide.

In addition to the above advantages, Applicant's device is simple in design and economical to manufacture. It is comprised of readily commercially available fabrics and materials. The foot plate provides added comfort and protection for the patient's foot, while the shroud completely conceals the Ilizarov fixator components. The shroud is easily removed, as at night, by simply pulling apart the Velcro™ seams.

While the invention has been shown in only one of its forms, it is not thus limited but is susceptible to various modifications without departing from the spirit thereof. 

1. An accessory device for an external orthopedic fixator used to stabilize a patient's foot and ankle, where the fixator has an external frame made tip of a plurality of frame components which surround the lower leg and ankle of a patient with one or more transfixation wires fixed thereto, the accessory device comprising: a foot plate having an upper surface used for supporting the sole of a patient's foot and having an oppositely arranged lower surface and an intermediate thickness, the foot plate having a plurality of connector elements mounted thereon, the connector elements having exposed upper extents extending upwardly from the upper surface of the foot plate, the upper extents being matingly engageable with at least one of the frame components of the fixator for securing the foot plate to the fixator and for supporting the patient's foot, the foot plate also having a peripheral outer edge which includes a connector region; a flexible shroud having an overall width and height, an exterior and an interior and a longitudinal seam which allows the shroud to be wrapped about the fixator with the fixator being received within the interior of the shroud, the shroud width and height being sufficient to conceal the fixator when the fixator is so received, the shroud having a lower peripheral edge which is provided with a connector region for matingly engaging the connector region of the foot plate, the longitudinal seam of the shroud also including a connector region for securing the shroud about the fixator.
 2. The accessory device of claim 1, wherein the footplate connector region and the shroud connector region are hook and loop type fabric connector regions.
 3. The accessory device of claim 2, wherein the connector region provided along the longitudinal seam of the shroud is a mating region of hook and loop type fabric connector fabric, the hook region being present along one exposed edge of the longitudinal seam and the loop region being provided along an oppositely arranged exposed edge of the seam.
 4. The accessory device of claim 3, wherein the shroud includes a shroud body which is formed of a synthetic fabric material, the interior of the shroud being provided with a layer of protective plastic which reinforces and protects at least a portion of the interior surface thereof.
 5. The accessory device of claim 4, wherein the connector elements which are provided on the footplate are threaded bolts which have exposed threaded extents which protrude upwardly from the upper surface of the foot plate, and wherein the frame component of the fixator which is used for securing the foot plate to the fixator and for supporting the patient's foot comprises at least one support collar having a plurality of openings therein, the openings being spaced in alignment with the exposed extents of the threaded bolts for receiving the bolts to thereby attach the foot plate to the fixator collar.
 6. The accessory device of claim 5, wherein the assembled foot plate and shroud completely enclose the fixator from beneath and on all sides.
 7. In combination, a fixator and accessory shroud, the combination comprising: an external orthopedic fixator used to stabilize a patient's foot and ankle, the fixator having an external frame made up of a plurality of frame components which surround a lower leg and ankle of a patient with one or more transfixation wires fixed thereto; and an accessory device made up of a foot plate and a shroud, the foot plate having an upper surface used for supporting the sole of a patient's foot and having an oppositely arranged lower surface and an intermediate thickness, the foot plate having a plurality of connector elements mounted thereon, the connector elements having exposed upper threaded extents extending upwardly from the upper surface of the foot plate, the upper extents being matingly engageable with at least one of the frame components of the fixator for securing the foot plate to the fixator and for supporting the patient's foot, the foot plate also having a peripheral outer edge which includes a connector region; the shroud having an overall width and height, an exterior and an interior and a longitudinal seam which allows the shroud to be wrapped about the fixator with the fixator being received within the interior of the shroud, the shroud width and height being sufficient to conceal the fixator when the fixator is so received, the shroud having a lower peripheral edge which is provided with a connector region for matingly engaging the connector region of the foot plate, the longitudinal seam of the shroud also including a connector region for securing the shroud about the fixator.
 8. The combination fixator and shroud of claim 7, wherein the footplate connector region and the shroud connector region are hook and loop type fabric connector regions.
 9. The combination fixator and shroud of claim 8, wherein the connector region provided along the longitudinal seam of the shroud is a mating region of hook and loop type fabric connector fabric, the hook region being present along one exposed edge of the longitudinal seam and the loop region being provided along an oppositely arranged exposed edge of the seam.
 10. The combination fixator and shroud of claim 9, wherein the shroud includes a shroud body which is formed of a synthetic fabric material, the interior of the shroud being provided with a layer of protective plastic which reinforces and protects at least a portion of the interior surface thereof.
 11. The combination fixator and shroud of claim 10, wherein the connector elements which are provided on the footplate are threaded bolts which have exposed extents which protrude upwardly from the upper surface of the foot plate, and wherein the frame components of the fixator which are used for securing the foot plate to the fixator and for supporting the patient's foot include at least one support collar having a plurality of openings therein, the openings being spaced in alignment with the exposed extents of the threaded bolts for attaching the foot plate to the fixator collar.
 12. A method of temporarily concealing an external fixator of the type used to stabilize a patient's foot and ankle, where the fixator has an external frame made up of a plurality of frame components which surround the lower leg and ankle of a patient with one or more transfixation wires fixed thereto, the method comprising the steps of: providing a foot plate having an upper surface used for supporting the sole of a patient's foot and having an oppositely arranged lower surface and an intermediate thickness, the foot plate having a plurality of connector elements mounted thereon, the connector elements having exposed upper extents extending upwardly from the upper surface of the foot plate, the upper extents being matingly engageable with at least one of the frame components of the fixator for securing the foot plate to the fixator and for supporting the patient's foot, the foot plate also having a peripheral outer edge which includes a connector region; providing a flexible shroud having an overall width and height, an exterior and an interior and a longitudinal seam which allows the shroud to be wrapped about the fixator with the fixator being received within the interior of the shroud, the shroud width and height being sufficient to conceal the fixator when the fixator is so received, the shroud having a lower peripheral edge which is provided with a connector region for matingly engaging the connector region of the foot plate, the longitudinal seam of the shroud also including a connector region for securing the shroud about the fixator; attaching the foot plate to at least a selected one of the fixator frame components so that the foot plate supports a patient's foot; wrapping the shroud about the fixator and the patient's lower leg, whereby the fixator is concealed within the interior of the shroud, the shroud being afixed to the foot plate by matingly engaging the connector region on the lower peripheral edge of the shroud with the connector region of the footplate, and securing the shroud about the fixator by matingly engaging the connector regions running along the longitudinal edges of the shroud seam. 